I have just bought an HP External Blu-Ray drive (model TS-23L). It seems to work fine with regular CD and DVD discs, but when I try to use a Ridata 25GB BD-R disc, my system says that the drive is empty--no disc installed! Is this because of the discs themselves, or is there some sort of hardware problem involved? Also, if it's the discs, can anyone recommend a brand of Blu-Ray disc that would work with this brand-new drive? Thanks in advance for any help or advice!